27 replies to this topic

[MDH]

Use them dry, but press the insides of tubes with paraffin wax. In small tubes like firecrackers, you can literally dip the entire device in a thin layer.

[Arthur Brown]

Hygroscopicity is a fact of certain compounds! Some go as far as deliquescence where the comp dissolves in the moisture it takes from the atmosphere. Sometimes high purity compounds have less problem, but not always. Protection such as waxes or resins or binders will have some effect but there will always be a stability issue with comps that might get damp and then get dry again.

[pyrotechnist]

Not going to let water dampen my day :>, marshmallows hmmm sound good mate lol but to tasty to stick in a tube and plus kids all over the place may come inspecting why they can smell marshmallows lol.

[dr thrust]

Anyone know how to make any chemical especially sugar none-hygroscopic? I thought about using wax or NC lacquer to coat the grains in a protective layer but not sure. One reason I want to do this is because I want my R-Candy to actually stay dry for once. Some of you may think, why not use a different chemical but then I aint sure what other chemical can achieve the same results as sugar but without absorbing so much water. Another one I want to damp proof is sodium nitrate.

i found this in the pages for afn, i don't advocate the method, im just reiterating the text
"wax coating stars"
heat ( on a hot plate) a small amount paraffin wax in a double boiler ( so the temp cant go above 100 degrees) when the wax has melted add a few stars at a time and mix stars around until they are coated.
then dump them on a piece of kraft paper to cool and separate, the wax coated stars are then ready to prime, using a standard round star making technique, ie a few stars in a bowl spray them with a 50/50 water alcohol mix, add prime, roll.
the author also graciously includes a formula for the prime
kn03 57.2
sulfur 11.4
airfloat char 11.4
silicon 11.4
dark ali 5.7
dextrin 2.9

Edited by chris m, 10 April 2010 - 01:15 PM.

[Mumbles]

This was in relation to dragon eggs. I heard some stories that people used to coat them in deck sealant. The idea was to waterproof them so nitrate wouldn't leach in during rolling or priming. The same thing may work for very hygroscopic salts.

[pyrotechnist]

Mite try them methods, how hygroscopic would sorbitol be compared to normal sugar? I am purely trying to make a none-hygroscopic sugar based lift powder as the gas output is better than normal BP and plus its a little simpler.

[seymour]

Mite try them methods, how hygroscopic would sorbitol be compared to normal sugar? I am purely trying to make a none-hygroscopic sugar based lift powder as the gas output is better than normal BP and plus its a little simpler.

If you are interested in Sorbitol, I'd check out Richard Nakka's website.

http://www.nakka-roc...y.net/sorb.html

If you don't mind patying for it, Potassium nitrate/ascorbic acid (Golden powder) sounds quite similar to what you are interested in doing.

[MDH]

Here is a thirteen year old recreational pyrotechnics post quoting a scientific study on black powder:

http://groups.google...61375657308?&q=

It seems to me like many organics will work (I have tried pretty much any organic mixture with nitrates I can possibly find, including dipropionates, sorbates, tartrates, etc) but polyphenols have a strong advantage. This doesn't surprise me at all. It seems like the kind of woods which contain high phenolic content are more reactive (Most recently, I tried charcoal from anise-stalks).

The distinctive advantage with these organics is that the potassium content can be controlled. With charcoal, there is no control over chemical content, so results vary.

The other advantage is that many of these aren't hard to obtain at all, and many phenolic or aromatic compounds can be bought in bulk quantities for very little.

So, your alternative lift does not have to be sugar.

[pyrotechnist]

What type of phenolic compounds are we looking at? I aint well up on them.

[Maxim]

I heard Cab-O-Sil is great at making mixtures less or not hygroscopic...

You just add 1 or 2% of composition weight to your composition. Correct me if i am wrong.

[dave]

I heard Cab-O-Sil is great at making mixtures less or not hygroscopic...

You just add 1 or 2% of composition weight to your composition. Correct me if i am wrong.

hi,
cabosil is "fumed" silicon dioxide, which is amorphous.
it is similar to a product called Aerosil made by degusa.
Now, ordinary cabosil or aerosil (aerosil 200) is actually hydrophilic
in order to render mixes hydrophbobic you need the hydrophobic version with added siloxane groups.
i think for the aerosil product this equates to Aerosil R972

SEE LINK
http://www.aerosil.c...es/default.aspx

there must be an equivalent Cabosil grade.
http://www.cabot-cor...S-720_09082.pdf

it is used primarily (in pharmaceuticals and of course pyro)as a flow aid in low (0.1 to 2%) although at higher concentrations some degree hydrophobicity will be confered to the mix.
because flow is improved, it will also pack down "quicker" as it were

dave321

[pyrotechnist]

The only phenolic compounds I have found from that documented you linked to MDH are quite poisonous and acidic or a known carcinogen. What other phenolics are they that are easily obtainable but not dangerous?

Wouldn't cab-o-sil at a high concentration decrease performance of the comp?

[pyrotechnist]

Did you get any success with Potassium Tartrate at all MDH? I just bought some and tried it but it doesn't seem to be producing any sort of reaction accept for a slight fizzing and molten blobs of oxidizer. Plus do you know of any safe phenolic compound?